Coma and Brain Death （昏迷與腦死）

1. Coma and Brain Death（昏迷與腦死） • Conscious – be aware or sensible of an inward state or outward fact （周知表裡的） • Consciousness （意識）– the state of awareness of self and environment (察覺自我及環境的狀態）and responsiveness to external stimulation and inner need • Coma（昏迷）-- Consciousness disturbance ( not conscious disturbance), Comatose ( not comatous)

2. 意識狀態：對本身和環境具有察覺與認知的能力意識狀態：對本身和環境具有察覺與認知的能力 客觀評估： 外表：清醒或睡眠 狀態 行動：自主及隨意性 ，對刺激有意義 的反應 昏迷：對本身和環境不具有察覺與認知的能力 客觀評估： 外表：睡眠狀 行動：對刺激不能產 生有意義的反應 意識狀態與昏迷

3. Brainstem RAS (mid-pons rostrally) and its projections to the hemispheres

4. Anatomic basis of coma (results from lesions that affect either the RAS or both hemispheres)

5. 意識之成分 • 喚醒度(Arousal):意識之原動力 1.臨床現象：外表上呈醒的狀態 (能主動睜眼或對外界刺激有睜眼反應） 2.是腦幹之網狀系統活動的表現 3.主為腦幹之功能 • 覺察能力(Awareness)：意識之內容 1.綜合認知和情感之腦功能 2.臨床現象：有意義的動作和語言 3.主為大腦半球的功能

6. Consciousness Disturbance(意識障礙) • Arousal / Level: maintained wakefulness by intact ARAS and both cerebral hemispheres Confusion Lethargy, Drowsy, Obtundation, Stupor, and Coma • Cognitive content: sum of mental function, leading to awareness of self and environment and the expression of psychological functions of sensation, emotion and thought  Confusion, Delirium, Delusion, Illusion, Hallucination etc.

7. Confusion State • “Clouding of sensorium” • Inability to think with customary speed and clarity, usually by some degree of inattentiveness and disorientation • Coexistent illusion, hallucination and delusion • Fluctuation (eg. Sundowning)

8. Glasgow Coma Scale (Teasdale & Jennett, 1977) • Eye Opening 4 - 1 • Verbal Response 5 - 1 • Motor Response 6 - 1

9. Eye Opening Spontaneous 4 To speech 3 To pain 2 None 1

10. Verbal Response Orientated 5 Confused 4 Words 3 Sounds 2 None 1

11. Motor Response Obeys commands 6 Localizing to pain 5 Withdrawal from pain 4 Flexion to pain 3 Extending to pain 2 None 1

12. 昏迷的原因 • 天幕上(supratentorial)病灶………………….. 20% • 天幕下(infratentorial)病灶…………………… 13% • 瀰漫性或新陳代謝(diffuse/metabolic)腦病 … 65% • 心因性(psychogenic)之無反應(假昏迷) ……. 2%  依據Plum and Posner (1980): （500例）

13. Causes of Consciousness Disturbance Howard RS (1995): 40% drug ingestion 25% hypoxic-ischemic insult 20% stroke – ICH, basilar a. thrombosis 15% general medical disorders

14. Goal of N.E. in Consciousness Disturbance • To establish the existence of clinical diagnosis of coma • To localize the neurologic lesion • To provide clues about underlying cause

15. Neurologic Examination in Consciousness Disturbance • Vital sings (TPR) and Skin before N.E. • Level of consciousness: GCS • Respiratory patterns: Cheyne-Stokes, hyperventilation, apneustic , ataxic • Brainstem reflexes: pupils, corneal reflex, reflex eye movements • Motor and reflex signs • Meningism

16. Abnormal respiratory patterns associated with pathologic lesions at various levels of the brain

17. Major brainstem reflexes used in the coma

18. Pupils in comtose patients

19. Brainstem pathways mediating conjugate horizontal eye movements

20. Caloric Test for Vestibular Function (30-100 cc ice water for oculovestibular reflexes in comatose patients)

21. Oculocephalic and Oculovestiblar reflexes in comatose patients with: (1) brainstem intact (doll’ head eye phenomenon) (2) bil. MLF involvement (3) and low brainstem lesion

22. Looking forward Looking to left Looking to right Convergence Internuclear Ophthalmoplegia (left MLF lesion)

23. Motor responses to noxious stimulation in acute cerebral dysfunction. A = Rt hemisphere B = Diencephalon C = Mibrain/Pons D = Medulla

24. Meningeal Signs: Neck stiffness, Brudzinski sign

25. Kernig Sign: Meningism or Lumbar Disc Herniation

26. Lumbar Puncture (CSF Exam):Meningitis or Subarachnoid Hemorrhage (SAH)

27. Probable Causes of Coma by N.E. • Brain stem intact: (-)lateralizing sign & (-)meningism Diffuse, metabolic, toxic encephalopathy ()lateralizing sign & (+)meningism Meningitis, SAH (+)lateralizing sign & (-) meningism  Supratentorial lesions • Brain stem dysfunction: Infratentorial lesion (brainstem or cerebellar) Herniation

28. 天幕上（supratentorial）病灶 • 最早出現的症狀通常為大腦局部障礙 • 漸進性之昏迷（因腦幹ARAS之進行性功能障礙所致） • 腦幹功能障礙由上而下進行： 間腦 中腦 橋腦 延腦 • 運動功能障礙常為兩側不對稱

29. 1. Cingulate (subfalcine) herniation 2. Transtentorial (central) herniation 3. Uncal herniation: uncus  edge of tentoriumIII & cerebral peduncle 4. Tonsillar herniation Supratentorial Mass with Brain Herniation

30. Uncal Herniation: coma withipsilateral oculomotor palsy and contralateral hemiplegia

31. Neurologic signs in coma with downward transtentorial herniation

32. 天幕下腔之病灶 • 突發性昏迷，或昏迷前先呈現腦幹之機能障礙 • 昏迷發生時，伴隨(或先有)局部性之腦幹徵候(brainstem signs) • 通常有顱神經之障礙 • 常常在早期即出現“奇異的”(bizarre)呼吸型態– hyperventilation,apneustic,ataxic

33. 瀰漫性/新陳代謝性腦病(Diffuse/Metabolic Encephalopathy • 精神混亂或輕度昏迷為最早出現之症狀 • 常有不隨意運動：asterixis, myoclonus, tremor, seizures etc. • 運動系統症狀通常為兩側對稱性 • 常發生換氣過度（hyperventilation）, Cheyne-Stokes respiration 或換氣不足（hypoventilation）之現象、酸-鹼不平衡 • 即使在昏迷狀態下，兩眼瞳孔縮小對光反應正常

34. 心因性（Psychogenic ）無反應（假昏迷） • 呼吸正常或換氣過度 • 兩眼做故意緊閉，手捏住病人鼻子會張口呼吸 • 兩側瞳孔對光反射呈收縮或擴張現象 • 眼前庭反射正常 • 肌肉張力正常或時緊時鬆 • 病態反射（Babinski sign）不會出現

35. Assessment and Management of Acute Coma – 1. Stabilization • Airway control • Oxygenation and ventilation • Adequate circulation (includes avoidance of hypotension in stroke) • Cervical stabilization – head injury or cervical trauma, RA

36. Assessment and Management of Acute Coma - 2. Coma Cocktail • Thiamine 100mg IV • Dextrose 50% 50 ml IV (may held if immediate fingerstick glucose available) • Naloxone 0.4-2.0mg IV or Flumazenil (Anexate) 0.3-0.6mg IV • Obtain blood for CBC, PT, PTT, chemistry panel, toxic screen, blood cultures

37. Assessment and Management of Acute Coma - 3. Threatening Conditions • Elevated ICP  head CT • Meningitis, encephalitis  LP, blood cultures • Myocardial infarction  EKG • Hypertensive encephalopathy  early therapy • Status epilepticus  EEG • Acute stroke  consider thrombolytic therapy

38. Outcome from Coma • Not possible to assess the prognosis with complete accuracy • Coma by drug ingestion  good prognosis • Traumatic coma > similar level of coma from nontraumatic causes • Prognostic factors in nontraumatic coma: etiology, depth & duration of coma

39. Assessment and Management of Consciousness Disturbance  Early Therapy for Threatening Conditions  To Prevent or Diminish Disability and Mortality

40. 腦死（Brain Death） • 死亡：呼吸停止、心跳停止和瞳孔放大且無反應 • 心肺輔助器及器官移植 • 1968 Ad Hoc Committee of the Harvard Medical School: brain death • 1971, Mohandas & Chou: brainstem death • 1976英國皇家醫學院訂定腦死的標準 • 1987 腦死判定程序(Brain Death Determination in Taiwan )

41. 大腦及腦幹之功能 • 大腦： 思考、記憶、認知、識別、意志、行為、 智力、語言、人格、情緒…等 意識之察覺能力（awareness） • 腦幹： 大腦與脊髓之間的神經路徑 司營自主呼吸、心跳及其它器官之神經中樞

43. Total Brain Death

44. Cerebral Death –Vegetative State

45. Vegetative State • Be awake, eyes opening, but no awareness of self or environment, • Unable to interact with others • No sustained, reproducible, purposeful or voluntary behavioral responses • Breathing spontaneously, normal brainstem reflexes • Inconsistent nonpurposive movements

46. Persistent Vegetative State (PVS)American Multi-Society Task Force • PVS: Vegetative state has continued for at least one month, but not imply permanency or irreversibility • Outcome of PVS: age, etiology, duration • 12 months after traumatic injury, 3 months after nontraumatic insult  PVS be permanent

47. Brainstem Death is Brain Death

48. Brainstem Reflexes for Coma

49. 診斷腦幹死之三步驟 • 符合必要的先決條件： 深度昏迷且沒有自主性呼吸，昏迷的原因為不能醫治之腦部結構損壞，而這種損壞會導致死亡 • 排除“具有可復原性”的昏迷病因： 低體溫、藥物中毒、代謝或內分泌障礙 • 無自主性呼吸(>12hrs)並試驗以確定無腦幹反射

50. 腦死 • 為了利用死者的器官進行移植 • 應嚴格規定並遵守診斷腦幹死之步驟 • 及其宣布死亡以免浪費可供移植之器官 • 腦幹死就是腦死及個體的死亡